Question

The silicate anion in the mineral kinoite is a chain of three $Si{O}_4$ tetrahedral that share corners with adjacent tetrahedral. The mineral also contains $C{a}^{2+}$ ions, $C{u}^{2+}$ ions, and water molecules in a 1 : 1 : 1 ratio mineral is represented as:

• A. $CaCuS{i}_3{O}_{10}.H_{2}O$
• B. $CaCuS{i}_3{O}_{10}.2H_{2}O$
• C. $C{a}_{2}C{u}_{2}S{i}_3{O}_{10}.2H_{2}O$
• D. none of these

Answer 1

The correct option is C $C{a}_{2}C{u}_{2}S{i}_3{O}_{10}.2H_{2}O$

Silicates shares corner, therefore, $S{i}_3{O}_{10}^{-4}$ will have a negative charge of $4$, so total positive charge should be 4. Also cations are in $1:1$ ratio so compound is $C{a}_{2}C{u}_{2}S{i}_3{O}_{10}.2H_{2}O$.